Abstract: The disclosed embodiments include shiftable covers, completion systems, and methods to shift a downhole cover in two directions. A shiftable cover includes a hollow interior configured to receive a diverter flowing in a first direction. The shiftable cover also includes a diverter seat disposed in the hollow interior and configured to retain the diverter. The shiftable cover also includes a plurality of segments configured to collapse in response to shifting of the shiftable cover from a first position to a second position to retain the diverter, and un-collapse in response to shifting of the shiftable cover from the second position towards the first position.

Abstract: The disclosed embodiments include pressure-activated firing heads, perforating gun assemblies, and methods to set off a downhole explosion. A pressure-activated firing head includes a first chamber and a second chamber having an energy storage element disposed within the second chamber. The pressure-activated firing head also includes a port fluidly connecting the first chamber and the second chamber. The pressure-activated firing head further includes a flow restrictor that restricts fluid flow from the second chamber to the first chamber. The pressure-activated firing head further includes a firing pin shiftable from a first position to a second position to strike an initiator. The pressure-activated firing head further includes a shear pin that holds the firing pin in the first position and configured to shear in response to a threshold pressure applied to the shear pin to release the firing pin from the first position.

Abstract: The disclosed embodiments include shiftable covers, completion systems, and methods to shift a downhole cover in two directions. A shiftable cover includes a hollow interior configured to receive a diverter flowing in a first direction. The shiftable cover also includes a diverter seat disposed in the hollow interior and configured to retain the diverter. The shiftable cover also includes a plurality of segments configured to collapse in response to shifting of the shiftable cover from a first position to a second position to retain the diverter, and un-collapse in response to shifting of the shiftable cover from the second position towards the first position.

Abstract: The disclosed embodiments include pressure-activated firing heads, perforating gun assemblies, and methods to set off a downhole explosion. A pressure-activated firing head includes a first chamber and a second chamber having an energy storage element disposed within the second chamber. The pressure-activated firing head also includes a port fluidly connecting the first chamber and the second chamber. The pressure-activated firing head further includes a flow restrictor that restricts fluid flow from the second chamber to the first chamber. The pressure-activated firing head further includes a firing pin shiftable from a first position to a second position to strike an initiator. The pressure-activated firing head further includes a shear pin that holds the firing pin in the first position and configured to shear in response to a threshold pressure applied to the shear pin to release the firing pin from the first position.